Bit sharpening mechanism



w. H. WINEMAN 2,404,201

BIT SHARPENING- MECHANISM July 16, 1946.

2 Sheets-Sheet 1 Filed Nov. 11, 1945 lizyz 0 fi 2 W 3 d 4/ a 8 a 2 87 22 3 5 M3 F0 I In 5 3 a n 2. I M a M A 2 3 L w 2 w Patented J uly' 16, 1 946 BIT SHARPENING BIEC HANISM Wade H. Wineman, Michigan City, IncL, assignor to Joy Manufacturing Company, a corporation of Pennsylvania Application November 11, casual No. 509,869

My invention relates to mechanisms for forming metallic articles, and more particularly to mechanisms adapted especially for forming cutting edges on drill bits.

In drilling rock by means of impact tools it is 5 a common practice to employ detachable drill bits having cutting edges which become dull as the drilling progresses but which may be reshar-pened a number of times before the bit needs to be discarded. tegrally formed bits after relatively short periods of use. As the cutting edges wear away and become dull the outer ends of the cutting edges also become rounded over, causing the bit to lose its gauge.- In resharpening the drill bit the cutting edges should be formedso that they'extend to the outer periphery of the bit, otherwise sufficient clearance for the bit will not be produced and a binding of the bit will take place. If the cutting edges of a detachable bit are sharpened by grinding them, as it has been the common practice to do, the amount of metal removed before the cutting edges extend to the periphery of the bit is such that the bit can be sharpened only a few' times before it must be discarded. If the cutting edges are subjected while hot to a rolling action which forces metal from the less Worn portions ofthe edges to the portions where the wear is greater and, at the same time, formsthe desired cutting edge, it will be seen that the life of the bit is materially increased.

It is proposed, in a preferred embodiment of the invention, to support a. suitable forming die member so that its axial center line assumes various angular positions relative to the axial center line of a bit which is supported in a stationary position. In other words, the forming die member is caused to nutate about a point in the axial center line of the bit. Means are provided for swinging the end of the die member remote from the bit in a circular path while the die member and the bit are forced firmly into engagement with each other, or at least one is forced firmly against the other. It will be seen that the same results may be obtained in various ways, for in- 4 stance the die member may be moved'to various angular positions in a fixed plane while the drill bit and the die member are caused to rotate about their respective axes, or, if desired, the die mem b-er may be held in a stationary position while 0 implement. Another object is to provide an im-' 21 Claims. (Cl. 76-5) It is also necessary to resharpen in- 10 2 proved mechanism for forming and sharpening the cutting edges of a rock drill bit. Stillanotherobject is to provide an improved implement form ing mechanism which operates to form the implement by forcing metal radially of the latter with a rolling action. Yet another object is to provide an improved hot rolling mechanism for forming the cutting edgesjof a drill bit by subjecting the cutting portions to a pressure moving radially of the cutting edges. A further objectis' to providean improved bit forming mechanism having a wabble or nutating member which is adapted to subject the cutting portions of the bit to a pressure which is applied at points moving radially of the cutting edges. These and other objects will appear more fully in the course of the following description.

, In the accompanying drawings, [have for purposes of illustration shown one embodiment which my invention may assume in practice.

In these drawings, Fig. 11s a side elevation of a bit forming mechanism embodying my invention.

Fig. 2 is an enlargedcross sectionalview taken on the plane of the line 2-2 of Fig.7.

Fig. 3 is an enlarged cross sectional view taken on the "pla'ne'of the line 3 -3 of Fig. '7. v

Fig. 4 is an enlarged cross sectional view taken on'the plane of theline i-4 of Fig.7.

Fig. 5 is an enlarged cross sectional view taken onthe plane of the line 55 of Fig. 7. I

Fig. 6 is a perspective view of the bit forming member.

Fig. 7 is an enlarged longitudinal vertical sectional view of a portion of the bit forming mechanism shown in Fig. 1.

Fig. 8 is a view like that of Fig; 7 but showing parts in different positions.

In the illustrative embodiment of my invention there is shown a vertical hollow, generally rectangular-shaped base 1 having a platform 2 on which a carriage '3' is reciprocably mounted. Formed along the sides ofthe platform are flanges 4 which extend into guideways 5 inthe carriage for holding the latter on the platform and limiting its movements to reciprocations in a path lying in horizontal planes and extending longitudinally of the basal. Suitable means are provided for moving the carriage 3 along the platform 2, and this means, as shown herein, includes a bell crank lever l pivotally supported by a shaft 8 carried by the side walls of the base I. The lever I has a short arm I0 connected by a link H to a lug l2 formed on theyfrorward end of the carriage}, and a long arm [4 connected by a link I to a lever I6 which is pivotally connected at one end to the lower portion of the base I. The lever I6 extends outwardly beyond its connection tothe link I5 and has an outer portion I8 adapted to be engaged by the foot of the operatorffor effecting a swinging of the bell crank leverl in a counterclockwise direction and a movement of the: carriage 3 to the left, as viewed in Fig. 1. A spring 20 is connected at one end to the base I and is connected at its other end to the lever I6 at a point between the ends of the latter. When the operators foot is removed from the lever I6, the spring 20 causes 7 the lever IE to swing upwardly'about its pivotal connection to the base and move the carriage 3 to the right along the platform 2. It will be understood that any suitable i'iuidv actuated means or any .other appropriate mechanical means may be provided, if desired, for moving the carriage 3 along the platform 2.

The carriage 3 is provided adjacent its ends with upstanding portions '22 and 23, and each of these portions has a cradle 24 receiving a bearing portion 25 which rotatably supports a tubular shaped member 2!. Attached to the upper ends of the portions 22 and23, as by bolts 28, are caps 2Band 33, each having a bearing portion 3I fittin over the member 21 and holding the latter for rotation on a fixed axis. Formed integral with the member 21 at opposite sides of the carriage portions 22 and 23 are annular flanges 32 which coact with the portions 22, 23 and their caps 29 and 39 for holding the member 21 against axial movement relative to the carriage 3. Suitable means are provided for rotating the member 2I, and this means, as shown herein, comprises a pulley 34 fixed to the outer end of the member 21 and connected by belts 35 to a pulley filifixed to the power shaft of a motor 31. While no such means is shown it will be evident that a clutch may be provided in the drive for the member 2! instead 'of controlling this drive by a switch in the power line to the motor 31.

Extending longitudinally through the tubular shaped member 21 and connected to the latter so'that'it will rotate as said member rotates is an arm 38 which is pivotally'connected at one end to the member 21 at a point 39' adjacent the rearward end of the latter. The other end of the arm extends'beyond the forward end of the mem- 3 ber 21, and the arm is guided, as by wall portions 43 formed on the member 21 near its forward end, so that it may swing within the tubular member 2I'about the pivot point 39, but still must rotate with this member. At the free endof the arm is an enlarged portion M to which a caplike element 42 is connected, as by bolts 63, and the portion II and the element 42 have recesses which cooperate to form a ball socket 44 which is adapted to receive a ball-shaped portion 45 1 U formed on one end of a chuck member 46. Formed is a collar 52 having diametrically opposite radial slots 54 which are adapted to receive rollers 55 forrengaging the cam surfaces 49', and the rollers 55 are supported by pins 56 extending through I openings 51 in the collar, as shown in Fig.

extend into the slots 50. Surrounding the collar is an annular groove 59 receiving a shipper ring 69, and pins 62 extending radially from the shipper ring are engaged by shipper arms 63 connected to a shaft 34 supported by the base I.

" the shipper ring 60. When the collar 52 is at the A manually operable lever 65 is connected to the shaft 64 for rotating the latter and efiecting a sliding of the collar 52 along the. member 21 through the action of the shipper arms 63 and left-hand end of the tubular member 21, as shown in Fig. 7, the arm 38 is held bythe rollers 55 so that itsfree end is spaced .angularly from the axis of the member 21. As the collar 52 is moved from its position shown in Fig. '7 toward the right,. the free end of the'arm 38 is moved nearer to the bit shown herein is ofthe winged type known as a cross bit in which the cutting edges extend. diametrically of the bit at right angles to each other, but it will be understood that this mechanism is adapted to form cutting edges on other types of bits. The socket I2 will be found to hold the bit l.I against turning on its axis; and it will be understood that the simple mechanism shown is merely illustrative of suitable clamping and receiving means for the heated bits to be sharpened; and, if desired, vice mechanisms hav ing suitable bit supporting dies may be used, these mechanisms being like thoseused on ordinary drill sharpeners for supporting the heated bits during abutting. See for example, the patent to Wineman 2,063,968. 1

The chuck member is provided with a recess 13 which is adapted to receive the polygonal shank I4 of a die I5 having, at its free end, V- shaped cross grooves It for forming the cutting edges on the bit. The bottoms of the grooves 16 are curved slightly toward the periphery of the die I5 so as to obtain a point of contact between the die and the drill bit moving radially of the bit uniformly with the variations in the angular displacement of the die relative to the drill bit. The periphery of the die adjacent its forward end is beveled in its portions between the grooves 16, as shown at I8, and these beveled portions the free end of the die is pressed firmly against the drill bit. The motor 31 is then started to rotate the tubular member 2! and'the arm 38.

The collar 52 iscaused to rotate with the tubular member 21 due'to the engagement of the rollers with the sides of the slots so in the member 21. As the member 27, the arm 38 and the collar 52 rotate, the shipper arms 63 are actuated by the tubular member.

along the tubular member causes the rollers 55 2, and r to roll along the cam surfaces 49 'and swing the arm 38 about its pivot point 39. When the arm is swung to its outermost position, as shown in Fig. '7, the die is caused to wabble at such an angle or nutate through such a path that pressure is applied successively to the cutting edges of the bit at their outermost ends. Of course when the orbit traversed by the ball joint is smaller, there is nonetheless work done on the bit. When the collar 52 is moved rearwardly along the member 21, the arm 38 'is swung toward the axis of the member 21 decreasing the wabble or range of nutation of the die and causing itto engage the cutting edges of: the bit nearer the center of the latter. Of course, as the angle of theaxial center line of the die to the axial center line of the work increases, the carriage 3 is fed forward to maintain contact with and pressure on the bit. As a result of my invention there is provided animproved mechanism for forming the cutting edges on drill bits. It will be seen that a gradual change in the angular positions of the die causes pressure to be applied to the bit at points moving gradually radially of the latter. Due to the curvature of the forming grooves on the die, the contact area between the surfaces on the bit'and the die are comparatively small for any angular position of the latter. Since the contact areas are small at any time, the pressure required to shape the edges is comparatively small. The radial movement of the points of contact results in a rolling action which forces metal in the direction of the points, forcing metal from the less wornportions to the portions where the wear is greater. Other advantages of the invention will be clearly apparent to those skilled in the art.

While I have in this application specifically described one embodiment which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration, and that the invention may be modified and embodiedin other forms without departing 4 ing die member having a working face adapted to engage the work at points spaced from the angular positions relative to said axial center line of the other of said members while the die member engages the work to befor'med, and means for actuating one of said members so that axial center line of the die member distances varying with the angle formed between said axial center line and the axial center line of said support member, adjustable means for supporting one of said members so that it may be positioned with its axial center line in different angular positions relative to said axial center line of the other of said members while the die member engages the work to be formed, and means for actuating said one of said members while its angular position of adjustment remains fixed with respect to said axial center line of said other member so that the axial center line of said one member generates a surface conforming to that of a cone.

2. In an apparatus of the character-described, in combination, a work support member, a forming die member having a working face adapted to engage the work at'points spaced from the axial center line of the die member distances varying with the angle formed between said axial center line and the axial center line of said support member, adjustable means for supporting one of said members so that it may be positioned with its axial .center line in difierent Lthe point of engagement between the work and said die member is caused to move about said axial center line of said die member while the angular position of said one member remains fixed with respect to the axial center line of said other member.

3. In an apparatus of the character described, in combination, a work support member, a forming die member having a working face adapted to engage the work at points spaced from the axial center line of the die member distances varying with the angle formed between said axial center line and the axial center line of said support member, means for moving said die member firmly into engagement with the work to be .formed, adjustable means for supporting said die.member so that its axial center line assumes different angular positions relative to said axial center line of said support member,

and means for. actuating one of said members so that the point of engagement between the work and said die member is caused to move in a path about said axial .center line of said die member. while the angular position of said latter member remains fixed with respect to the axial center line of said support member.

4. In .an apparatus of the character described, in combination, a worksupport member, a forming die member engageable with the work, means for adjustably supporting said die member so that it axial center line assumes different an,- gular positions relative to the axial centerline of said support member and embodying means for holding said die member in its adjusted position with respect to the axial center line of said support member, means for moving said die member into engagement with the work, and means for actuating one of said members so as to effect a movement of the point of engage-' ment between the work and said die member in a fixed" path about said axial center line of.

said die member.

5. man apparatus of the character described;

in combination, a Work support member, a form.-'

ing die member engageable with the work, means for adjustably supporting said die member so that its axial center line assumes difierent an-. gular positions relative to the axial center line-- or said support member, means for movingsaid die member into engagement with the work, and means for actuating said die member when the latter is held in any one of its different angular positions so as to effect a movement of the point of engagement between the work and the die member in a fixed path about said axial center line of said die member.

6. In an apparatus of the character described, in combination, a work support member, a forming die member, means for adjustably supporting one of said members so thatthe angle formed by V the axial center line of said die member with the axial center line of said work support member may be varied and embodying means for holding said one member in its adjusted position, means for moving one of said members so as to effect an engagement between the work and said die member, and means for actuating one of said members when said die and support members are held in any one of their different relative angular positions so as to effect a movement of the point of engagement between the work andsaid die member in a path about said axial center line of said die member.

7. In an apparatus of the character described, in combination, a work support member, a forming die member having a working face adapted to engage the work at points spaced from the axial center line of the die member distances varying with the angle formed between said axial center line and the axial center line of said support member, means for supporting said die member in engagement with the work and with its axial center line in different angular positions rel: ative to said axial center line of said support member, and means formoving the end of said die member remote from the work in a circular path when said die member is .held fixed in any one of its difierent angular positions.

8. In an apparatus of the character described, in combination, a work support member, a forming die member having a working faceadapted to engage the work at points spaced from the axial center line of the die member distances varying with the angle formed between said axial center line and the axial center line of said support member, means for supporting said die member at a point spaced from the work while the latter is engaged by said die member, means for adjusting bodily said supporting means so that said axial center line of said die member assumes different angular positions relative to said axial center line of said support member. and means for moving said supporting means in a circular path while the angular position of said die member is maintained fixed with respect to the axial center line of said support member. 9. In an apparatus of the character described, in combination, a work support member, a forming die member having a working face adapted to engage the work at points spaced from the axial center line of the die member distances varying with the angle formed between said axialcenter line and the axial center line of said support member, means for supporting said die member with its working face in engagement with the work, means for adjusting said supporting means so that said axial center line of said die member assumes different angular positions relative to said axial center line of said support member, and means for moving said elongated die member having a working face,

at one end engageable with the work, a rotatable member supported with its axis perpendicular to the face of the work, a supporting arm pivotally connected at one end to said rotatable member, means for operatively connecting the other end of said supportin arm to said die member at the end of the latter remote from the work, said connecting means permitting rotation of said supporting arm relative to said die member, means for swinging said supporting arm about its pivotal connection to said rotatable member,and means for rotating said rotatable member. o

7 11, In an apparatus of the character described,

in combination, a Work support member, a

forming die member engageable' with the work, a rotatable tubular member supported with its axisperpendicular to :the face of the Work, a

supporting arm extending through said tubular memberand pivotally supported at one end by the latter, means for operatively connecting the other end of said supporting arm to said die member at a point spaced from the work, means slidably mounted on said tubular memberoand engaging said supporting arm for swinging the latter about'its pivot, means for sliding said last mentioned means along said tubular member, and means for rotating said tubular member.

12-. In an apparatus of the character described, in combination, a work support member, an elongated die member having a die ortion at one end engageable with the face of the work and movable relative thereto for effecting metal flow to form the surfaces of the Work, an element supported for rotation on an axis perp n dicular to the face of the work, means for moving said element axially relative to the work, sup! porting means pivotally connected to said element to swing relative thereto and operatively engaging at pointsspaced from its ivot the other end of said die member in a manner to permit relative rotation between said supporting means and said die member during rotation of said element, and means for rotating said element.

13. In an apparatus of the character described, in combination, a work support member, a form ing die member having a die portion engageable with the work, an element supported for rotation on an axis perpendicular to the face of the work, means for moving said element axially relative to the Work, supporting means for said diefmem ber including an elongated member pivotally connected at one end to said element and oper atively connected at its other end through a universal joint to said die member, and means' for rotating said element.

14. In an apparatus of the character described,

in combination, a work support member, a forming die member having a die portion engageable with the work, an element supported for rotation on an axis perpendicular to the face or the work, means for moving said element axial1y relative to the work, supporting means for said die member including an elongated member pivotally connected at one end to said element and operatively connected at its other end through a universal joint to said die member, means for swinging said elongated member about its pivotal connection to said element during rotation of the latter, and means for rotating said element.

15. In an apparatus of the character described, in combination, a work support member, a forming die member having a die portion engageable with the work, an element supported for rotation on an axis perpendicular to the face of the work, means for moving said. element axially relative to the work, supporting means, for said die member including an elongated member pivotally connected at one end to said element and operatively connected at its other end to said die member, means for swinging said elongated member about its pivotal connection to said element, said last mentioned meansincluding cam surfaces on said elongated member die actuating member alined with the center line of said bit supporting device, a universal joint carried by said rotating die actuating member "and having means for displacing it towards and from the axis of rotation of the latter, die sup porting means carried by one part of said universal joint, a die having its forward end loosely receivable in said bit receiving socket, and

j means for advancing said die actuating member towards said bit supporting device as the distance between the universal joint' and the axis of rotation of said actuating member increases.

18. In an apparatus of the character described, in combination, a stationary work support member, an elongated die member having a working face at one end adapted to engage the work at points spaced from the axial center line of the die member distancesvarying with the angle formed between said axial center line and the axial center line of said support member, means loosely supporting the other end of said die member and adjustable to position said die member with its axial center line in different angular positions relative to said axial'center line of said support member, and means for moving said supporting means to cause the portion thereof which supports said other end of the die member to move in a circular path about said axial center line of said support member while said die member is held against rotation about its own axia1 center line by reason of its engagement with the work, said adjustable means being adjustable at the will of the operator during movement of said supporting means in said circular path.

19. In an apparatus for forming the wings and cutting edges of a rock drill bit, a support for the drill bit, a forming die having surfaces for formingportions of theiwinge and the cutting edges on the wings of the drill bit, means for supporting said forming die in operative forming relation with respect to the drill bit with the axial center line of said die disposed the drill bit, means effective when said die is supported by said supporting means in operative forming relation with the drill bit to move said die to cause its axial center line to trace a path lying in a surface of a cone, and means operative during aforesaid movement of said form ing die for changing the angular relation of the axial center line of said die with respect to the axial center line of the drill bit to vary the forming action of said die on the drill bit.

7 20. In an apparatus for forming the Wings and cutting edges of a rock drill bit, a support for the drill bit, a forming die having surfaces" for forming portions of the wings and the cutting edges on the wings of the drill bit, means for supporting said forming die in operative forming relation with respect to the drill bit with the axial center line of said die disposed at an angle relative to the axial center line of the drill bit, means effective when said die is supported by said supporting means in operative forming relation with the drill bit to move said die to cause its axial center line to trace a path lying in a surface of a cone, means operative.

during aforesaid movement of said forming die for changing the angular relation of the axial center line of said die with respect to the axial center line of the drill bit to vary the forming action of said die on the drill bit, and means" for moving said forming die in an axial direction relative to the drill bit concurrently with the change in angle of said die with respect to the drill bit thereby to maintain said die in operative forming relation with respect to the drill bit.

21. In a forging machine, the combination comprising a work support, a die member hav-- ing a die portion at one end, a rotatable support coaxial with said work support, supporting means pivotally mounted on said rotatable support to swing relative thereto and pivotally connected to the other end of said die member, means for adjusting said supporting means into difierent angular positions about its pivot relative to said rotatable support to vary the inclination of said die member with respect to the axial center line of the work, and means for rotating said rotatable support and said supporting means to cause the axial center line of said die member to move in a path lying in at an angle relative to the axialcenter line of the surface of a cone, said adjusting means being operable at will during rotation of said rotatable support and said supporting means to change the 1 inclination of said die member.

WADE H. WINEMAN. 

